The discussion below is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.
The present invention relates to a method of manufacturing a foldable bag for use in a bag-in-box assembly, the foldable bag having a folded condition in which it includes at least an inwardly creased bag portion in a longitudinal direction thereof.
Such a method is known from the international application WO 2004/022440. According to the known method a foldable bag is manufactured, which has, in a folded condition, a rectangular shape and two inwardly creased bag portions in its longitudinal direction at opposite sides of the bag. The bag is composed of four sheets. The four sheets are positioned with respect to each other according to a predetermined pattern and welded at a bottom side and a top side which are opposite to each other in longitudinal direction of the bag such that the inwardly creased bag portions are created along two side edges opposite to each other in lateral direction of the bag.
The bag thus manufactured is fixed to a box. In mounted condition a lower part of the bag in the box lies on the bottom of the box. Each inwardly creased bag portion forms one compartment in the bag below and one above the inwardly creased bag portion. During filling of the bag with a liquid it should be unfolded and obtain the shape of the container. During filling of the bag the liquid may flow into the compartments of the bag which are located above as well as below the inwardly creased bag portions. If the compartment of the bag above the inwardly creased bag portion is filled more quickly than that below it, the liquid contained in the compartment above the inwardly creased bag portion will press thereon such that filling of the lower compartment becomes more difficult. It is observed that this effect may result in incomplete unfolding of the bag.